Rapping-plate for wooden patterns



(N0v Model.)

D. FRASER. RAPPING PLATE FOR WOODEN PATTERNS.

N0. 457,991 Patented Aug. 18, 1891.

fMW 3 Ma UNITED STATES PATENT OFFICE.

.DONALD FRASER, OF MILWAUKEE, \VISCONSIN.

RAPPING-PLATE FOR WOODEN PATTERNS.

SPECIFICATION forming part of Letters Patent No. 457,991, dated August18, 1891.

Application filed August '7, 1890- To all whom it may concern.-

Be it known that I, DONALD FRASER, of Milwaukee, in the county ofMilwaukee, and in the State of Wisconsin, have invented certain new anduseful Improvements in Rapping-Plates for \Vooden Patterns; and I dohereby declare that the following is a full, clear, and exactdescription thereof.

My invention relates to rapping-plates for wooden patterns, and it willbe hereinafter more fully described, with reference to the accompanyingdrawings, and subsequently claimed.

In the drawings, Figure 1 representsa plan view of one style ofrapping-plate; Fig. 2, a longitudinal section taken on line 2 2 of Fig.1, and Fig. 3 a plan view of another style of rapping-plate. Fig. 4represents a peculiar form of draw-bar.

Referring by letter to the drawings, A represents a rapping-plate madefrom malleable iron, cast-steel, or other elastic metal. The edges ofthe plate are preferably beveled from top to bottom, and are alsocorrugated.

When the edges of the plates are beveled, the under side of eachcorrugation has a radius equal to that of a standard bit; but owing tosaid bevel the radius of the upper side of said corrugation is slightlygreater. All the corrugations may have an equal radius, as shown by Fig.1, or the radii of said corrugations may be varied, as shown by Fig.

The plates A are formed with countersunk openings 0 for the heads of thescrews by which said plates are secured to the wooden patterns. Theplates are also provided with an opening d, in which to insert arappingpin, and another opening e, that is tapped to engage a screw-threaded bar such as is usually employed as a handle by which to draw awooden pattern from the sand.

The rapping-plates are made in various sizes, according to the patternson which they are to be employed.

The sockets for the plates are made by boring into the wooden patternswith bits of the standard gage, and thus said sockets can be Serial No.361,309. (No model.)

mered into the desired shape; but plates made in this manner areexpensive and add materially to the cost of the patterns. My plates arecast in the desired shape, and con sequently they require no hand-workexcept the tapping of the draw-holes,'and should a plate be broken itcan be readily replaced by a new one at a small cost.

The plates above described are cast in various sizes and shapes to suitthe trade, and the draw-holes being tapped said plates are put in lotsfor the market, thus forming an improved article of manufacture andcreating a new industry.

As a matter of fact, patterns are usually required in the foundry assoon as finished, and rapping-plates are seldom thought of until thelast moment. Therefore it follows that, because of the time required tofashion such plates, the latter are omitted and the patterns hurried tothe foundry and soon returned for more or less expensive repairs. Myrapping-plates being standard articles, to be carried in stock, arealways ready, and can be very quickly attached to the patterns, wherebyvexatious delays and expense are saved.

The bar B (shown in Fig. 4) is provided with a tapered screw-point f ofstandard size at the extremity, the increasing diameter serving to takeup wear in the tapped openings of the rapping-plates, whereby a rigidconnection is always possible between said bar and a plate, this beingessential to successful drawing of a pattern.

Having thus fully described my invention,

what I claim as new, and desire to secure by In testimony that I claimthe forego1ng I Letters Patent, iS have hereunto set my hand, atM1lwaukee, 1n :0 As an improved article of manufacture, a the county ofMilwaukee and State of \V1s rapping-plate having corrugated edgesbevcousin, in the presence of two witnesses.

eled inward from its upper face and formed DONALD FRASER. with a seriesof countersunk openings there- \Vitnesses:

in, a threaded opening, and a rapping-pin N. E. ()LIPHANT,

opening, substantially as described. M. KLUG.

